1. Field of the Invention
The present invention relates to a receiver which receives message information, or a so-called paging receiver (also called a pager).
2. Description of the Related Art
FIG. 26 is a block diagram showing the electrical configuration of a conventional paging receiver 1. A signal transmitted from an information service carrier by wireless transmission or the like is received by an antenna 4, and tuned and detected by an RF unit 5. The detected signal is demodulated and then supplied to a decoder unit 6.
In the decoder unit 6, a destination ID code is obtained from a pager format signal of, for example, the POCSAG system, and it is judged whether the ID code coincides with the own ID code stored in an ID-ROM 7 or not. If the codes coincide with each other, message information is obtained from a signal which is subsequently received. Furthermore, an interrupt signal indicative of reception of an effective signal is outputted.
In response to the interrupt signal, a control unit 2 activates operation programs which are previously stored in a program memory 3, such as those for processes of storing and displaying the received message. The received message information is stored in a received message storing unit 8, and displayed on an LCD (liquid crystal display) 10 which is driven by an LCD driver 9.
When execution of a process such as message deletion is instructed through a key input unit 11, the process such as deletion is conducted on the received message. A vibration generating unit 12 notifies the user of reception of a message by a vibration, and an alarm/melody sound generating unit 13 acoustically notifies the user of reception.
The control unit 2, the program memory 3, the decoder unit 6, the received message storing unit 8, the LCD driver 9, the key input unit 11, the vibration generating unit 12, and the alarm/melody sound generating unit 13 are electrically connected to each other via a bus line 14.
FIG. 27 shows a message 15 which is transmitted from an information service carrier and received by the paging receiver 1. FIGS. 28A to 28C show in stages display screens 16a to 16c in the case where the message 15 is displayed on the LCD 10. In the paging receiver 1, a data indicative of the reception date and time is stored together with the message 15 in the received message storing unit 8. Therefore, the reception date and time is displayed on the LCD 10 in addition to the message 15.
Since the display capacity of the LCD 10 is limited, the whole of a message is not always displayed. A message number 18, the message 15, and the reception date and time 19 are set to be total data to be displayed. A display virtual area 17 which includes these data is assumed. As shown in FIGS. 28A to 28C, in the actual display screens 16a to 16c which are smaller than the display virtual area 17, the data are displayed in a split manner.
The display screens 16a to 16c are switched over by operating a display message downward button 20a and a display message upward button 20b.
Another example of a pager of the prior art is disclosed in Japanese Unexamined Patent publication JP-A 7-131840 (1995). The pager is provided with a ROM for classifying received messages in accordance with the contents, so that the stored received messages can be quickly searched. Specifically, messages are classified by the kind of the end of a sentence. For example, a message ended by "KUDASAI (please)" is stored as "Instruction" category, that ended by "SHIMASU (will do)" is stored as "Memo" category, and that ended by "TAI? (would you?)" is stored as "Question" category.
In accordance with increasing requests of the user for the variety and amount of information, the paging service is advancing so as to provide a wide variety of and a large amount of information. In a paging receiver, the capacity of a memory for storing received messages is made larger. It is difficult to select a necessary message from such a large amount of received messages.
In the pager disclosed in Japanese Unexamined Patent Publication JP-A 7-131840 (1995), all received messages are stored, and it is difficult to select a necessary message as described above, thereby producing problems in that the operability is lowered, and the memory capacity is wastefully used. Moreover, the pager has a further problem in that necessary messages cannot be stored in an increased number.
Furthermore, messages are classified only by the kind of the end of a sentence. In order to correctly classify a message, the sender of a message must prepare the message in consideration of this classification system. If such consideration is not sufficiently performed, there arises a disadvantage that the message cannot be classified. Since a ROM is used for classification, the user cannot freely change the classification category.